'''Coiled-coil X-ray structure at 1.17 A resolution'''
===Coiled-coil X-ray structure at 1.17 A resolution===
==Overview==
<!--
We determined the 1.17 A resolution X-ray crystal structure of a hybrid peptide based on sequences from coiled-coil regions of the proteins GCN4 and cortexillin I. The peptide forms a parallel homodimeric coiled-coil, with C(alpha) backbone geometry similar to GCN4 (rmsd value 0.71 A). Three stabilizing interactions have been identified: a unique hydrogen bonding-electrostatic network not previously observed in coiled-coils, and two other hydrophobic interactions involving leucine residues at positions e and g from both g-a' and d-e' interchain interactions with the hydrophobic core. This is also the first report of the quantitative significance of these interactions. The GCN4/cortexillin hybrid surprisingly has two interchain Glu-Lys' ion pairs that form a hydrogen bonding network with the Asn residues in the core. This network, which was not observed for the reversed Lys-Glu' pair in GCN4, increases the combined stability contribution of each Glu-Lys' salt bridge across the central Asn15-Asn15' core to approximately 0.7 kcal/mole, compared to approximately 0.4 kcal mole(-1) from a Glu-Lys' salt bridge on its own. In addition to electrostatic and hydrogen bonding stabilization of the coiled-coil, individual leucine residues at positions e and g in the hybrid peptide also contribute to stability by 0.7 kcal/mole relative to alanine. These interactions are of critical importance to understanding the stability requirements for coiled-coil folding and in modulating the stability of de novo designed macromolecules containing this motif.
The line below this paragraph, {{ABSTRACT_PUBMED_12824486}}, adds the Publication Abstract to the page
(as it appears on PubMed at http://www.pubmed.gov), where 12824486 is the PubMed ID number.
-->
{{ABSTRACT_PUBMED_12824486}}
==About this Structure==
==About this Structure==
Line 22:
Line 26:
[[Category: Ivaninskii, S.]]
[[Category: Ivaninskii, S.]]
[[Category: Coiled-coil]]
[[Category: Coiled-coil]]
''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Sat May 3 04:51:05 2008''
''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Tue Jul 29 02:39:48 2008''
Revision as of 23:39, 28 July 2008
This article has been automatically seeded. Changes to this page should pertain to the PDB entry only and not to the protein or biomolecule in general.
